Iron rich dusts derived from various steelmaking processes have been generally thought to be the common iron oxide Fe.sub.2 O.sub.3. These ducts are wastes, with limited use for such minor purposes as a hardener for cement. There have been attempts at reclamation for recycling to steel furnaces. U.S. Pat. No. 3,895,088, issued July 15, 1975, to Michigan Technological University identifies and describes these ducts.
It is well known that hydrogen sulfide gas may be extracted from hydrocarbon gas by reacting with iron compounds; for example, sour fuel gas is pumped through trays of wood chips impregnated with Fe.sub.2 O.sub.3. Likewise, hydrocarbon gas may be bubbled through an aqueous solution of iron hydroxides, with the following reaction: EQU 2Fe(OH).sub.3 +3H.sub.2 S.revreaction.Fe.sub.2 S.sub.3 +6H.sub.2 O
The reaction product Fe.sub.2 S.sub.3 is unstable; regeneration is to be expected.
In my earlier co-pending applications previously referred to, I disclosed a quite different type of iron oxide particle characterized by exceptional porosity and created by the partial oxidation of iron to Fe.sub.3 O.sub.4. This may be used for sweetening gas by making a water slurry of such particles and bubbling the gas through the slurry, with stable products of reaction. In my earlier application, now U.S. Pat. No. 4,008,775, I disclosed that such porous particles are advantageously used as an additive to water based muds in the drilling of wells.